<PRE><B>Question 1032168</B>
n/2-3n/4+5n/6 = 21 
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Multiply thru by 12 to get rid of the fractions.
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6n - 9n + 10n = 12*21
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7n = 12*21
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n = 12*3
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n = 36
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Cheers,
Stan H.
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